The two elements that make up the largest percentage by mass of earths crust are oxygen and ?

Explain why process 2 is so important to sexual reproduction identify processes 1 and 3 state one difference between the cells produced by process 1 and cells produced by process 3

How do living things obtain phosphorus

8) animals respond in various ways to stimuli detected through their senses. some of these responses are stimulated by the presence of danger. which of these animal responses is the best example of a response to an immediate threat? a) a rooster crows every morning at the first sign of light. b) as something approaches an octopus, it shoots a cloud of ink. c) from late fall until spring, bears hibernate to preserve energy. d) a dog is getting hot in the sunlight, so he moves to a shaded area.